The amount of sleep that elementary school children get per night follows a Normal distribution with a mean of 9.5 hours and a standard deviation of 0.55 hours. Find the proportion of elementary school children who get between 9 and 10 hours of sleep per night. Sketch the Normal curve and shade the area under the curve that is the answer to the question.

1. why is a frequency distribution useful? it allows researchers to see the "shape" of the data. it tells researchers how often the mean occurs in a set of data. it can visually identify the mean. it ignores outliers. 2. the is defined by its mean and standard deviation alone. normal distribution frequency distribution median distribution marginal distribution 3. approximately % of the data in a given sample falls within three standard deviations of the mean if it is normally distributed. 95 68 34 99 4. a data set is said to be if the mean of the data is greater than the median of the data. normally distributed frequency distributed right-skewed left-skewed